Wednesday, August 27, 2008

Seriousness of allergy rhinitis

By: AlexChong

What is actually allergy rhinitis? Allergy rhinitis is an allergic disease, which is caused by the sensitinogen that reacting on the mucous membranes in the nasal cavity. It consists two types that are perennial and seasonal allergic rhinitis. Perennial allergic rhinitis occurs throughout the year; whereas, seasonal allergic rhinitis usually occurs during the blossoming or flowering season. In this season, plants start to release their pollen for breeding purpose. Pollen is one of the sensitinogens to the allergic rhinitis. Clinical features of allergic rhinitis are; itching in the nose, sneezing, watery nasal discharge and nasal obstruction. There are about 20 % of adults and children have seasonal or perennial allergic rhinitis [Otolaryngol Head Neck Surg 1986;94:470-5]. Although it is prevalence in most of the countries regardless tropical or seasonal, most of the conditions are not treated adequately and the consequence is that allergic rhinitis becomes chronic. The chronic state of allergic rhinitis usually will lead to more serious complications of the upper and lower airways such as asthma, sinusitis and otitis media with effusion. Otitis media is an inflammation of the middle ear. Fluid is built up in the middle ear and causes temporary lose of hearing. However, if this chronic disease is not treated properly, it may lead to permanent hearing impairment.

A few medical scientists had carried out surveys to study the epidemiologic links between allergic rhinitis and other airway diseases. What they had found out were, 78% of patients who had asthma were also had allergic rhinitis [Allergy 1983;38:25-9]. They also found out that 99% of adults and 93% of adolescents, who had allergic asthma, also had allergic rhinitis [J Allergy Clin Immunol 1997;99:S138]. Besides, the other study that had been carried out for 23 years was found out that college students who previously had allergic rhinitis had three times higher the possibility to have asthma compared to those students who had not had allergic rhinitis before [Allergy Proc 1994;15:21-5].

Many researches and works had been carried out to study the epidemiologic link between allergic rhinitis and sinusitis. The results had been well documented. The earlier study showed that 53% of children, who had allergic rhinitis, also had sinusitis [J Allergy Clin Immunol 1978;61:310-4]. They proved this from the children abnormal sinus radiographs. Whereas, recent study showed that up to 70% of children, who had allergy and chronic rhinitis, had abnormal sinus radiographs [J Allergy Clin Immunol 1988;82:935-40]. 78% of the patients who had recurrent sinus infection, rhinitis allergy was coming together with their extensive sinus disease. For the children who had otitis media with effusion, 40 to 50% of them had allergic rhinitis [J Allergy Clin Immunol 1997;99:S787-97.]. This was confirmed by positive allergy skin tests or increased serum IgE antibodies to specific allergens test.

Scientist had proposed a model for the development of sinusitis and otitis media. Their proposed model assumes that the earliest cause for sinusitis is not bacterial infection but it is due to the obstruction in the nasal cavity, which hinders the normal movement of air and secretions in and out of sinuses. Virus that causes nasal inflammation is upper respiratory tract infection (URTI) type, which is called rhinovirus. Research had been carried out to study the effect of this virus to the nasal diseases. The result showed that when rhinovirus is inoculated into the nasal passage of a group people, one third of these people would develop sinus abnormities and typical sinus disease symptoms [J Allergy Clin Immunol 1992;90:474-8]. Another study also showed that 87% of healthy adult, who voluntarily went through self-diagnosed colds, had maxillary sinuses illness [Engl J Med 1994;330:25-30].

Fluid inside the sinus cavity must be drained normally to keep the nasal healthy. When nasal being infected by bacteria or virus, or exposure to allergen, dust or chemicals, thicken secretion will be developed and it has higher possibility blocks the narrowed sinus ostia (opening that connect to the sinus cavity). Accumulation of these secretions in the sinus cavity will lead to further obstruction, mucosal swelling and also thicken the sinus mucosa. This will create an anaerobic environment that further favorite the bacterial growth and lead to infection. Congested sinus ostia must be resolved if not, it will lead to recurrent acute and eventually chronic nasal disease. This model also explained why chronic sinusitis is resistant to the antimicrobials treatment alone. To treat the sinusitis properly, antihistamines and corticosteroids have to be used as a combination with the antimicrobials treatment.

A similar model had been developed by scientist to explain the occurrence of otitis media with effusion. 83% of the children had at least once occurrence of acute otitis media by the time they reach 3 years old [J Infect Dis 1989;160:83-94]. This model hypothesizes that nasal inflammation that is caused by allergens or URTIs virus will further cause inflammatory swelling and obstruction of the Eustachian tube. Obstruction of the Eustachian tube will increase negative pressure in the middle area and without improper ventilation; fluids will accumulate in the middle ear. Obstructed Eustachian tube will open occasionally with an effusion and this will suck the inner nasal secretion, which contain bacteria, virus and allergens into the middle ear cavity. Consequently, this will cause acute bacterial otitis media.

From the information above that have been gathered from various scientific publications, we know that common nasal allergy should not be left untreated. This is because it will lead to obstruction, fluid accumulation, bacterial infection and acute disease. If these diseases are not treated properly or successfully, a chronic state of inflammation, nasal congestion, and sinus infection will be developed and it can cause mucosal damage and ultimately, chronic disease. If the disease spreads to the middle ear, it will cause permanent hearing impairment

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